House Extensions
Sooner or later, most homeowners will be faced with the decision of either moving to a new house or having a home extension built. Home additions are often perceived as costly and complex projects, but they needn't be so.

Why Investing in a House Extension Makes Sense
Home additions can represent a radical improvement to your property and quality of life.
- Extensions add value: strategically planned home extensions can add value to your property. A 2014 study revealed that some additions (like conservatories) can deliver returns as high as 108 per cent. Median profits ranged between £12,000 (loft addition) and £2,300 (additional bathroom). The same study concluded that the average house extension adds £30,000 (or 10 per cent) to the value of a home. But what if you are not planning on selling your home?
- Home extensions can be beneficial even if you plan to stay put. Added value cannot always be quantified in terms of financial rewards, and in many cases a professionally done house extension will bring you and your family better quality of life. The simple fact of having additional space can make your home environment much more enjoyable.
- Extensions are generally cheaper than moving homes: when faced with a shortage of space, investing in a home extension can ease off the financial burden entailed in moving to a new home. This is particularly applicable to properties in high-value locations, such as London and parts of Surrey and the South East.
- Build it now, reap the benefits later: the costs involved in construction work will continue to increase for the foreseeable future. Adding to your now means that you will have additional space available when you need it (birth of a child, elderly parents moving in, etc.) and at a comparatively lower cost.
Home extensions: Rules and regulations
Generally speaking, going for a home addition is less stressful and less time-consuming that moving homes. However, the many rules and regulations involved in home extensions can make the process seem more complex than it really is. Here are some resources to help you save time and figure out which regulations apply to you.
Do I need planning permission?
Generally speaking, home extensions do not require planning permission as long as:
- They take up less than 50 per cent of the land area around the property
- They do not extend beyond the highest point of the roof
- They are single-storey side extensions
- They do not include balconies or verandas
- They fall within the stipulated limits (4/3 metres for rear extensions on detached / attached properties respectively; 4 metres upper height limit for side extensions; two-storey extensions no closer than 7 metres from the property's rear boundary). Visit this site for a detailed overview of the current planning permission limits and conditions.
Outbuildings are generally exempt from planning permission unless a property is part of a listed building or on designated land. If your home extension requires planning permission, you can file a planning application online. Please note that planning permission requirements apply to properties in Wales. To learn about planning permission requirements in Scotland, check this guide. For information of the requirements applicable to Northern Ireland, visit this link.
Do's and don'ts
Do work with qualified professionals
Extension plans must be drawn up by an architect that is registered with the Architects Registration Board. To find qualified builders and tradesmen, you can use tools provided by the Homeowners Alliance.
Do shop around
Always get as many quotes as possible, bearing in mind that the average cost of building work ranges between £1,000 and £1,600 per square metre. Don't forget that all construction work in the UK is subject to an additional 20 per cent VAT charge.
Don't forget about the Neighbour Consultation Scheme
Since May 2013 and for a period of 6 years, any single-storey extensions must range between 4 and 8 metres (detached homes) and between 3 and 6 metres (all other homes). Any work above these limits must go through the Neighbour Consultation Scheme. Homeowners must notify their local authorities.
Don't overlook building regulations
In addition to planning permission, consider whether building regulations apply to your extension project. Most conservatories and small detached buildings are exempt.